1. First macroscopic animal fossils: Neoproterozoic Era (1 Billion–542 Million Years Ago)
Early members of the animal fossil record include the Ediacaran biota (from Ediacara Hills of Australia), which dates from 565 to 550 million years ago.

2. Paleozoic Era (542–251 Million Years Ago)
The Cambrian explosion (535 to 525 million years ago) marks the earliest fossil appearance of many major groups of living animals (about half of all extant phyla arose in Cambrian)
There are several hypotheses regarding the cause of the Cambrian explosion and decline of Ediacaran biota
New predator-prey relationships
A rise in atmospheric oxygen
The evolution of the Hox gene complex

3. Pangea 300mya

4. Animal diversity continued to increase through the Paleozoic, but was disrupted by mass extinctions.
Animals began to make an impact on land by 460 million years ago.
Vertebrates made the transition to land around 365 million years ago.

5. Mesozoic Era (251–65.5 Million Years Ago)
Coral reefs emerged, becoming important marine ecological niches for other organisms.
During the Mesozoic era, dinosaurs were the dominant terrestrial vertebrates.
The first mammals emerged
Flowering plants and insects diversified

7. Cenozoic Era (65.5 mya - Present)
The beginning of the Cenozoic era followed mass extinctions of both terrestrial and marine animals.
These extinctions included the large, nonflying dinosaurs and the marine reptiles.
Mammals increased in size and exploited vacated ecological niches.
The global climate cooled.
Chicxulub asteroid

8. Cambrian Explosion Chicxulub meteor, K-PG extinction – end of dinos
Triassic – appearance of dinosaurs and mammals.
Pangea starts to breatk into Gondwana and Lurasia
PT Extinction – 90% of all marine and 70% of all
terrestrial species go extinct
Pangea
1st Vertebrates on land
“Age of Fish” (Devonian)
Cambrian Explosion

9. Shocked quartz
110mi wide, 12mi deep
Irridium dust cloud layer. Meteorites can contain as much as 470ppb,
most crust has ~0.4ppb. The clay layer on the K-PG boundary around
the world has 6ppm

10. Percent of marine species to go extinct in a given time.

11. “Spindle diagram” showing the numbers of families of major vertebrate
clades since the Cambrian.

12. Body plan and symmetry
Animals can be categorized according to the symmetry of their bodies, or lack of it
Some animals have radial symmetry, with no front and back, or left and right
Two-sided symmetry is called bilateral symmetry

13. Body plan and symmetry Bilaterally symmetrical animals have
A dorsal (top) side and a ventral (bottom) side
A right and left side
Anterior (head) and posterior (tail) ends
Cephalization, the development of a head
Radial animals are often sessile or planktonic (drifting or weakly swimming)
Bilateral animals often move actively and have a central nervous system

14. Body plan and symmetry

15. Tissues
Animal body plans also vary according to the organization of the animal’s tissues
Tissues are collections of specialized cells isolated from other tissues by membranous layers
During development, three germ layers give rise to the tissues and organs of the animal embryo

16. Sponges and a few other groups lack true tissues
Diploblastic animals have ectoderm and endoderm
These include cnidarians and ctenophora
Triploblastic animals also have an intervening mesoderm layer; these include all bilateria:
flatworms, arthropods, vertebrates, and others
Endoderm – develops into GI tract (except mouth, pharynx, anus),
glands of GI tract including liver, lungs, thyroid, and thymus,
urinary bladder, urethra
Ectoderm – develops into epidermis, nervous tissue, nephridia
Mesoderm – other organs and structures (muscle, cartlidge, bone,kidneys,
gonads, heart, blood vessels, blood cells, etc

17. Radial symmetry animals have 2 Germ layers
Ectoderm is the germ layer covering the embryo’s surface
Endoderm is the innermost germ layer and lines the developing digestive tube, called the archenteron

18. Bilateral symmetry animals have 3 Germ layers
Ectoderm is the germ layer covering the embryo’s surface
Endoderm is the innermost germ layer and lines the developing digestive tube, called the archenteron
Mesoderm is the middle germ layer

22. Body cavities
Most triploblastic animals possess a body cavity (deuterostomes and protostomes)
A true body cavity is called a coelom and is derived from mesoderm
Coelomates are animals that possess a true coelom

23. Body cavity formed from mesoderm
Body cavity formed from mesoderm and endoderm
NO body cavity

24. Coelomates and pseudocoelomates belong to the same grade
A grade is a group whose members share key biological features
A grade is not necessarily a clade, an ancestor and all of its descendants

25. Protostome and Deuterostome development
Based on early development, many animals can be categorized as having protostome development or deuterostome development

26. Protostome and Deuterostome development
Protostomes are all
other bilateria
Deuterostomes are echinoderms and chordates

27. Protostome and Deuterostome development
Distinguished based upon differences in…
Cleavage
Coelom formation
And the fate of the blastophore

28. archenteron
archenteron

30. Animal phylogeny
Phylogenies can be constructed using molecular, morphological and fossil data.
The book attempts to discuss the differences of morphological and molecular data phylogenies.

31. Major molecular and morphological data points of agreement
All animals share a common ancestor
Sponges are basal animals
Eumetazoa is a clade of animals (eumetazoans) with true tissues
Most animal phyla belong to the clade Bilateria, and are called bilaterians